Flexural strength is a principal factor that defines the fatigue life of face gear.A new tooth structure with circular arc of fillet part for the face gear tooth are developed and a shaper with tooth rounded top is applied to generate the fillet part of helical face gear.The thesis derived the equations of fillet surface of the shaper.The coordinate systems are created for the face gear machining

with which the equations of fillet surface of face gear is conducted from the equations of rounded top of the helical shaper.Two versions of finite element model of tooth surfaces of face gear are generated.One version is based on the cutting shaper with tooth top peak and another version is the new structure of the shaper surface with addendum rounded top.Tooth contact analysis（TCA） and loaded tooth contact analysis（LTCA） for the two versions of face gear drives with helical spur gear are also considered.The results of simulation show that the bending stress of tooth surface of the face gear with fillet surface generated by the rounded top of the shaper is lower 12% than the first version’s.